I just switched from a 85mph speedo cluster to a 145mph cluster and everything works fine except the oil pressure gauge pegs as soon as I start the car.is this a bad gauge?thanks for any help.

 

The wire that is comming from the oil sending unit isnt connected to the gauge correctly. Your bad connection could be behind the gauge. This happened to me once, but my bad connection was near the sending unit.

Hope this helps!

 

yeh Im gonna check the connection at the sending unit.Before swapping the gauges I was by the sending unit re-routing my plug wires,maybe I hit something.thanks

 

Mine is usually pegged too. But its all original. Havent changed anything. Ive had the car about 10 years and it has always been that way. I turn it on and the oil pressure almost pegs out. I hit the gas and it hits the peg.
Its a '91 Firebird. 3.1L v-6. 270,000 original miles. I use to worry about it, but never could figure out what, if anything, was wrong.

 

Mine was just the connector knocked off,I figured it out last night.the blade that makes the connection inside the rubber boot had pulled out.all fixed now.thanks to the person who mentioned this.If yours pegs when you hit the gas,you have another problem,maybe the sending unit is bad?not sure

 

Gm is known for bad oil sending units, look into getting a new one if it pegs when you hit the gas. It should move some, but not peg out.

 

If I read his post properly he said his gauge almost pegges out, then completly pegs when he hits the gas.
Sounds like a bad gauge to me.

 

Maybe some of y'all just have really good oil pressure????

 

Try replacing the oil pressure sending unit yet?

It's right next to the dist, on the back of the engine..

Costs about $15...